In message <00e401c599c1$0ee0f990$0100a8c0@ivp2000>
          Jinx <joecolquitt@clear.net.nz> wrote:

> Bearing in mind what you said, my experience is that carbide /
> carbide-cobalt are good value.

Until you break one. They're essential for glass fibre (FR4) laminates - =
HSS
bits tend to overheat and dull quite quickly. Carbides "just work" and
usually last for a few thousand holes.

> I used to use HSS a long time
> ago but found you don't really get a lot of holes out of them. I
> hate to think how many thousands of holes (not as a pro PCB
> maker, but in a "I want a board and I want it now" capacity")

The only real reason to keep a home PCB fab. "I want that board in two ho=
urs,
not two weeks!"

> I've drilled over the years with just a couple of carbide bits

I'm a clumsy oaf - I've broken about a dozen so far, partially thanks to
trying to use them at 2000RPM in a drill with naff bearings and a chuck t=
hat
was mounted at some odd angle to the motor shaft. The bits really don't s=
eem
to like that... [sarcasm] I wonder why... [/sarcasm]

Given that I've just spent near enough =A370 on a Dremel and a new drill =
stand,
I'd expect to break a few less bits... At =A34.20 a throw, they're not ex=
actly
cheap. Then again, I didn't pay =A34.20 each for mine (see other message =
in
this thread) :)

Later.
--=20
Phil.                              | Acorn RiscPC600 SA220 64MB+6GB 100ba=
seT
philpem@philpem.me.uk              | Athlon64 3200+ A8VDeluxe R2 512MB+10=
0GB
http://www.philpem.me.uk/          | Sony MZ-N710 NetMD Minidisc
... Hailing frequencies open Mr. Worf. - Hi, this is Steve Wright on 1 FM.
--=20
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